LAUSR

Turbulent momentum flux in the typhoon boundary layer was measured at a turbulent flux tower in Southeast China using an eddy covariance technique during the passage of typhoons Fanapi and Megi in 2010. The anemometers were mounted on the cantilever bracket at the height of 26.6 m, 42.4 m, 60.4 m and 82.9 m. The momentum flux in the typhoon boundary layer decreased with increasing height during the two typhoon passages. The decrease was nearly linear during the passage of the Typhoon Fanapi. However, in the boundary layer of the Typhoon Megi, the momentum flux at 26.6 m height was much greater than that at 42.4 m height. The cospectra of wind components showed that the enhanced flux at the bottom of the boundary layer was caused by small scale turbulence with frequency in the range of 0.1–1 Hz and can be explained by the turbulent energy accumulation of small scale turbulence. This article is protected by copyright. All rights reserved.